The invention relates to an impregnating agent for convoluted boots consisting of a thermoplastic or elastomer material and to such convoluted boots which are impregnated with such an impregnating agent. Such convoluted boots are frequently used for covering the chamber of a joint, which joint chamber is filled with a lubricating agent; they prevent lubricating agents from leaving the joint chamber, while preventing dirt from entering the joint chamber. Such convoluted boots are often used for rotating joints incorporated into vehicle drivelines. The two end collars of the convoluted boot enclose a shaft on the one hand and a joint component on the other hand, to which shaft and joint component respectively they are clamped by tensioning strips.
At large joint articulation angles, the folds of the convoluted boots which are also articulated are deformed to such an extent that their outer surfaces contact one another. If this causes relative movements between the surfaces, the resulting friction has two undesirable effects: thus it cannot be avoided that, if dirt enters, the abrasive effect at the outer surfaces of the folds, in time, is responsible for the removal of material, as a result of which the service life of the convoluted boot is reduced. In addition, in the case of convoluted boots with a running time in the vehicle of less than 10,000 km, a squeaking noise is identifiable if water is added, which is regarded as adversely affecting comfort.
From DE 43 01 062 C1 there is known a convoluted boot which is provided with a surface coating consisting of poly alpha olefins in order to reduce the friction between the surfaces of the boot wall which contact one another at large articulation angles. When dirt particles are present as well, such a surface coating is removed within a short time, so that if a joint with a high load spectrum is subjected to large articulation angles, an improvement is achieved for only a certain period in service life of the convoluted boot.
U.S. Pat. No. 4,830,767 proposes a lubricating grease for driving joints which are covered by a convoluted boot. The purpose of said grease is to protect the elastomer of said convoluted boots against breaking and becoming brittle during long periods of wintry operation. Furthermore, it is mentioned that said grease constitutes a good lubricating agent between metal parts on the one hand and elastomer plastics on the other hand. It is proposed that poly alpha olefins are used as a base for such a grease. However, to achieve the desired effects, it is necessary to add a combination of carbonate and phosphate additives.
U.S. Pat. No. 5,223,161 describes a grease for the same type of application, which grease is based on poly alpha olefins, with a package of additives consisting of sulphate and an aliphatic monocarboxylate.
From U.S. Pat. No. 4,967,609 there is known a convoluted boot consisting of a rubber material, which boot comprises a closed coating or individual annular elements which are permanently applied to the surface of the folds, with the coating or the individual annular elements consisting of a rubber material constituting the carrier substance and of an anti-degradation agent which are to be diffused into the surface of the convoluted boot.
U.S. Pat. No. 4,573,693 describes a convoluted boot for covering constant velocity universal joints, which boot comprises a coating layer consisting of polyamide resin which is glued to the base member by means of a primer coating. The purpose is to reduce wear by means of a coating consisting of a different material, which coating is glued on to the base member.
U.S. Pat. No. 4,265,663 proposes to apply a wax compound consisting of a liquid poly alpha olefin and a liquid silicon to rubber and elastomer hoses and connectors to protect same and thus render same durable. The liquid silicon is used in the form of an aqueous emulsion.
From the unpublished DE 196 19 368.0 there is known a convoluted boot impregnated with an agent consisting of hydrocarbons with a molecular weight of  greater than 200.